Study: Only 2.5% of Israelis infected with corona, country far from ‘herd immunity’

First serological survey testing for coronavirus antibodies reveals national infection rate is 2.5 percent. Results mean 200,000 Israelis were infected, but most had few or no symptoms.

By Paul Shindman, World Israel News

The results of the first widespread serological blood testing of Israelis has revealed a massive infection rate 10 times higher than the known cases to date, Channel 12 News reported Tuesday. However, it’s a drop in the bucket when talking about herd immunity.

The results of the nationwide test to determine how many Israelis have been exposed to the coronavirus showed the exposure rate in the county is 2.5 percent (or about 200,000 Israelis).

The testing was done by the IDF’s Epidemic Treatment Team in collaboration with Israel’s National Center for Disease Control and took blood samples from 1,700 people of different ages from all over the country. The blood was tested for virus antibodies, the presence of which indicate the person had been infected even though they may have had only mild symptoms or no symptoms at all.

“We looked at the proportion of antibodies in the blood of the subjects and thus the study reveals the level of immunity of the population in Israel. It gives us a more accurate picture of the ratio,” said Professor Danny Cohen, who heads the School of Public Health at Tel Aviv University.

“The bottom line is that 2.5 percent of the population was found to have antibodies to the virus, which means they contracted corona and most of them experienced it as a minor disease,” Cohen said.

Researchers said the results are not encouraging because they indicate that Israel is far from “herd immunity.”

“For herd immunity, at least 50 percent of the population needs to develop antibodies and currently that exists for only 2.5 percent, meaning we are far from herd immunity and the health system must be prepared in terms of epidemic management and not be surprised by outbreak groups as we now see in the [high school in Jerusalem],” Cohen said.

That school was closed last week after several staff and students tested positive. By Tuesday morning after the entire school was tested health officials determined a total of 129 students, 19 staff members and 25 other people they had come in contact with had so far contracted coronavirus.

“If we perform the serological sampling every two or three months, it will be possible to track the accumulation of exposures, some new cases, data to help manage the epidemic,” Professor Cohen added.

Most schools reopened on May 14 after two months of closures and restrictions had brought new infections in Israel down to near zero. However, the infection rate picked up last week and at least two dozen schools around the country have been closed again after local outbreaks, with students and staff being told to self-isolate.

Parents complained that health guidelines to wear masks and keep social distancing were not being enforced in the schools.

On Tuesday morning an infected student at a school in Beer Sheba caused the school to be closed and 1,930 more schoolchildren were sent for preventative isolation.